1. Field of the Invention
The invention relates to ventilated shipping cartons, and more particularly to ventilated cartons for transporting fruit, vegetables, or the like, which combine spaced, wood veneer slats forming the carton body, with corrugated fibreboard top and bottom closures.
2. Description of the Prior Art
Many fruits and vegetables continue to breath and generate heat after they have been harvested and the continued build-up of heat during shipment has rendered essential the use of strong, ventilated cartons capable of securely holding the produce during long shipments in refrigerated railway cars, or trucks, while permitting flow of cool air to circulate through and about the individual cartons to carry off the generated heat and prevent spoilage.
For many years, slatted wooden crates have been used as a satisfactory means of transport, an early design of which is disclosed in U.S. Pat. No. 488,997 issued to J. W. & A Glidewell in 1893. This crate utilized solid wood end walls, spaced slats running from end to end forming the ventilated remaining walls, and four strengthening and spacing wood cleats upon the side and end walls near each end. Some forty years ago an improved version of this crate came into nearly universal use and involved thinner slats arranged vertically, thinner end walls, the same or greater number of cleats, and a plurality of wires wound horizontally about the side and end walls to bind and strengthen the crate.
Because of the shortage of wood veneer for slats, particularly hard wood which takes so long to grow, and the vastly increased cost, corrugated and wax treated fibreboard cartons have tended to replace wire-bound boxes for many applications during the last twenty years. Examples of ventilated cardboard cartons which have been proposed are disclosed in U.S. Pat. No. 1,767,629 issued to Walter and U.S. Pat. No. 3,863,831 issued to Wozniacki et al. The disadvantages of the cardboard cartons with respect to wire-bound wood crates are reduced stacking strength, perviousness to water and refrigerating chemicals or gases, poorer ventilation and loss of reusage capability.
It has been proposed to use a combination of wood and fibreboard container, as for example disclosed in U.S. Pat. No. 2,293,361 issued to Roberts. The box of this patent comprises a box-like outer fibreboard container, a tubular, inner fibreboard liner, a pair of resilient fibreboard side walls reinforced with wood slats forming inner side walls and a pair of fibreboard, inner end walls encased in wood frames. While the described construction results in a strong, fruit protective box, it is of complex and expensive construction, utilizes a great deal of scarce and expensive wood and provides no ventilation. Another combination wood, cardboard container is revealed in U.S. Pat. No. 3,197,108 issued July 27, 1965 to P. D. Northway. This container comprises a corrugated, slotted cardboard box whose end walls each include a cardboard sheet to which is glued a wood cleat for stacking strength. While this box provides ventilation and improved stacking strength, the strength of the side walls is not comparable to that of the wirebound wood crate.